iptest3 with IPython - ipython

Question

I'm brand new to Python programming and trying to get myself a functional base from which I can run things like the IPython Notebook which looks pretty exciting.
Thus far I have both Python 2.7 and 3.3 from python.org installed in OS X 10.6 (Snow Leopard) as well as ActiveTcl 8.5.13. Almost everything that I've tried thus far works as expected. I'm focused on learning 3.3, but want to have the option of using 2.7 too. I read up in several documents that I need to start gaining access to PyPI packages using a Python package manager and that distribute is the one I should use for 3k. So I installed that according to the documentation I found and it seemed to work fine.
I also installed pip as directed, and a number of others.
At this point, I have:
$ pip freeze
distribute==0.6.34
ipython==0.13.1
nose==1.2.1 (installed after IPython)
pexpect==2.4 (installed after IPython)
pyflakes3k==0.4.3
readline==6.2.4.1 (installed after IPython)
At this point, I'm doing this from ipython.org guidance
And when I did $ easy_install pexpect, I got a bunch of errors:
$ easy_install pexpect
Searching for pexpect
Reading http://pypi.python.org/simple/pexpect/
Reading http://pexpect.sourceforge.net/
Reading http://sourceforge.net/project/showfiles.php?group_id=59762
Best match: pexpect 2.4
Downloading http://pypi.python.org/packages/source/p/pexpect/pexpect-2.4.tar.gz#md5=fe82d69be19ec96d3a6650af947d5665
Processing pexpect-2.4.tar.gz
Writing /var/folders/td/td0Sh8EfGFuMCnKex1v+q++++TI/-Tmp-/easy_install-s4dtyy/pexpect-2.4/setup.cfg
Running pexpect-2.4/setup.py -q bdist_egg --dist-dir /var/folders/td/td0Sh8EfGFuMCnKex1v+q++++TI/-Tmp-/easy_install-s4dtyy/pexpect-2.4/egg-dist-tmp-5h5cg4
File "build/bdist.macosx-10.6-intel/egg/fdpexpect.py", line 36
raise ExceptionPexpect, 'The fd argument is not a valid file descriptor.'
^
SyntaxError: invalid syntax
File "build/bdist.macosx-10.6-intel/egg/FSM.py", line 77
return `self.value`
^
SyntaxError: invalid syntax
File "build/bdist.macosx-10.6-intel/egg/pexpect.py", line 82
except ImportError, e:
^
SyntaxError: invalid syntax
zip_safe flag not set; analyzing archive contents...
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pexpect-2.4-py3.3.egg/fdpexpect.py", line 36
raise ExceptionPexpect, 'The fd argument is not a valid file descriptor.'
^
SyntaxError: invalid syntax
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pexpect-2.4-py3.3.egg/FSM.py", line 77
return `self.value`
^
SyntaxError: invalid syntax
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pexpect-2.4-py3.3.egg/pexpect.py", line 82
except ImportError, e:
^
SyntaxError: invalid syntax
Adding pexpect 2.4 to easy-install.pth file
Installed /Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pexpect-2.4-py3.3.egg
Processing dependencies for pexpect
Finished processing dependencies for pexpect
That looks bad to me (although I don't yet have the expertise to really interpret it), and so I'm not sure if I have a complete install of pexpect.
After installing nose (before pexpect as per URL above), I tried running iptest and iptest3 from the command line, and both failed to find the command, but after I did easy_install ipython again (after nose), I noticed that this install added iptest3 (as well as ipcluster3 and a few other scripts) to my path, and now my bash shell can find iptest3, but when I run it, I get some more bad-looking output:
$ iptest3
Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/3.3/bin/iptest3", line 9, in <module>
load_entry_point('ipython==0.13.1', 'console_scripts', 'iptest3')()
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/distribute-0.6.34-py3.3.egg/pkg_resources.py", line 343, in load_entry_point
return get_distribution(dist).load_entry_point(group, name)
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/distribute-0.6.34-py3.3.egg/pkg_resources.py", line 2308, in load_entry_point
return ep.load()
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/distribute-0.6.34-py3.3.egg/pkg_resources.py", line 2014, in load
entry = __import__(self.module_name, globals(),globals(), ['__name__'])
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/IPython/__init__.py", line 43, in <module>
from .config.loader import Config
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/IPython/config/__init__.py", line 16, in <module>
from .application import *
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/IPython/config/application.py", line 31, in <module>
from IPython.config.configurable import SingletonConfigurable
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/IPython/config/configurable.py", line 26, in <module>
from .loader import Config
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/IPython/config/loader.py", line 27, in <module>
from IPython.utils.path import filefind, get_ipython_dir
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/IPython/utils/path.py", line 25, in <module>
from IPython.utils.process import system
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/IPython/utils/process.py", line 27, in <module>
from ._process_posix import _find_cmd, system, getoutput, arg_split
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/IPython/utils/_process_posix.py", line 22, in <module>
from IPython.external import pexpect
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/IPython/external/pexpect/__init__.py", line 2, in <module>
import pexpect
File "/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages/pexpect-2.4-py3.3.egg/pexpect.py", line 82
except ImportError, e:
^
SyntaxError: invalid syntax
After doing all that, I noted that my /Library/Frameworks/Python.framework/Versions/Current had been pointing to 2.7, and I guessed that that might be related to my problems and changed the symbolic link to point to 3.3, but iptest3 still fails with the error above.
Any other thoughts on what to do to fix this? It's clear that iptest is pretty important to doing anything else (like IPython Notebook) I want to do.

Answer 1

There is a py3-compatible fork of pexpect called pexpect-u (the u is for unicode, the main difference between the two). You need this to run the pexpect-based parts of IPython on Python 3.
Should be a simple
pip install pexpect-u
side note: pexpect-u is by IPython developer Thomas Kluyver, who did most of the heavy lifting bringing py3 compatibility to IPython.